This invention relates to heat treating and more in particular pertains to a heat treating process to improve the corrosion resistance of an aluminum plate on a substrate.
It has been found that an aluminum plate deposited on a substrate substantially in accord with the process of Schmidt et al., U.S. Pat. No. 3,462,288, occasionally develops corrosion in a plurality of spaced apart locations after an extended period of exposure to the ambient atmosphere. The isolated points of corrosion have become known as pinholes in the aluminum plate. It is desirable that a process be developed to minimize such pinhole formation.